Good read online read on gnupg?

[Adi Linden]

Hi,

I am muddling my way through gnupg. I am successfully encrypting user data 
on a webserver which is attached to an email. I can also encrypt it once 
it's been received. Yeeeeepie...!!!

Now that my curiousity has been awakened, I am trying to understand how 
all this business with signing, trust and keyservers works. I read the 
"The GNU Privacy Handbook" and a few howtos. Unfortunately they're just 
that, guides on how to do it. I still don't understand the concept - how 
and why things are done.

Any suggestions on what's good to read?

Thanks,
Adi